According to Carlotta Flores, the owner of the El Charro restaurant in Tucson, the cash and letter arrived in an unassuming envelope in the mail last week. In the letter, a woman who had worked for her in the 1990s while attending the University of Arizona, admitted to regularly stealing money from the restaurant by not charging for drinks.

"One of the waiters I worked with had encouraged me to 'forget' to ring in a few drinks a shift and pocket the cash. And for some stupid reason, I did it," the woman wrote in the note. "I grew up in the church, I knew better. I hadn't stolen a dime before then, nor have I since."

"Thankfully, I was a terrible waitress and you all fired me before it could amount to more than a few hundred dollars total," the mysterious letter writer added.

"It's been 20 years, but I still carry great remorse. I am very sorry that I stole from you. Please accept my apology + this money as a repayment + 20 years of interest. May God forever bless you + your family."

Carlotta's son, Ray, posted the letter to his Facebook page on Saturday, saying the letter made his week.

Flores told KVOA that the letter was deeply moving to her and her employees, and helped renew her faith in people after having a tough week.

"I had my purse stolen and this sort of renewed the faith that we had a lot of good people out there," Flores said. "I don't know where she's at or who she is but I will tell you one thing. I hope that she's read or has seen what an impact this has made not only on me, my family, my business but where it will go in the future so I hope she keeps looking to see what we're doing with it."